Level sensor offset mounting mechanism

Abstract

A level sensor offset mounting mechanism that mounts in the tank fill pipe of an underground fuel tank and provides an offset for the lower level sensor portion from the drop tube. The level sensor offset mounting mechanism connects to an inner wall of the tank fill pipe by a connector. A conduit extends vertically downward from the connector to a position below the top of the tank. At the lower end of the conduit, a selectively rotatable offset device provides a horizontal offset away from the drop tube. The offset device may be rotated to an insertion position, wherein no offset is provided, to facilitate insertion, or extraction, of the level sensor into the tank. Connected to the offset device at an end distal the connection to the upper portion, the lower portion of the level sensor measures the fuel and water levels within the tank. This lower portion generally includes an instrumentation housing, a lower conduit, a fuel level float, a water level float, and a magnetostrictive device for determining the positions of the floats. The level sensor offset device is designed such that electrical wiring may be passed therethrough without allowing fuel vapors to escape the tank.

I claim: 
     
       1. A level sensor offset mounting mechanism comprising: an upper conduit;   a connector means for connecting the upper conduit to a tank fill pipe;   said connector means constructed to receive an electrical wiring therethrough;   said upper conduit extending downward from said connector means;   said upper conduit having a lower end;   a lower portion for measuring the fluid levels within a tank;   a rotatable offset means for selectively providing horizontal offset of said lower portion from said upper conduit;   said lower portion attached to and extending downward from said rotatable offset means;   said rotatable offset means proximal said upper conduit lower end; and   a locking means for locking said rotatable offset means in either an offset position wherein said lower portion is horizontally offset from said upper conduit or an insertion position wherein said lower portion is not offset from said upper conduit.   
     
     
       2. A level sensor offset mounting mechanism as claimed in claim 1 wherein said connector means comprises: a body having a pipe wall contact face, a top end, and a bottom end;   said pipe wall contact face having an opening therein;   said opening extending horizontally at least partially through said body;   a vertical cavity in said body;   said vertical cavity extending from said bottom end and intersecting said opening;   said opening and said vertical cavity constructed to receive and transmit said electrical wiring therethrough.   
     
     
       3. A level sensor offset mounting mechanism as claimed in claim 2 wherein said pipe wall contact face is convexly arcuate and constructed to conform to an inner wall of said tank fill pipe. 
     
     
       4. A level sensor offset mounting mechanism as claimed in claim 2 wherein said body further comprises: an inner face opposite said pipe wall contact face;   a slot in said inner face; and   said slot providing access to said vertical cavity throughout said slot's length.   
     
     
       5. A level sensor offset mounting mechanism as claimed in claim 2 wherein said connector means further comprises: a threaded nipple having a cavity therethrough;   said opening having threads therein;   said threaded nipple threadably engaging said opening; and   said threaded nipple constructed to secure said body to said tank fill pipe and receive said electrical wiring therethrough.   
     
     
       6. A level sensor offset mounting mechanism as claimed in claim 1 wherein said lower portion comprises: an instrumentation housing attached to said rotatable offset means;   a lower conduit;   an annular water float slidably positioned on said lower conduit;   said annular water float constructed to float at the water level within said tank;   an annular fuel float slidably positioned on said lower conduit;   said annular fuel float constructed to float at the fuel level within said tank;   said annular fuel float positioned above said annular Water float; and   a position measuring means for transmitting the position of said annular water float and said annular fuel float to said instrumentation housing.   
     
     
       7. A level sensor offset mounting mechanism as claimed in claim 1 wherein said rotatable offset means comprises: a hinge frame fixedly attached to a lower end of said upper conduit;   said hinge frame including two spaced parallel side walls and at least one connector wall;   said at least one connector wall extending between said side walls;   each of said side walls having an exterior surface distal said opposite side wall;   a side wall opening in each of said side walls having an axis;   said side wall openings substantially axially aligned;   an extension body;   said extension body including two spaced parallel flanges, an elongated extension arm, and an attachment means for attaching said extension body to said lower portion;   each of said flanges having an interior surface proximal said opposite flange;   each of said flange's interior surface slidably positioned adjacent to and in contact with said exterior surface of said side walls;   a flange opening in each of said flanges having an axis;   said flange openings substantially axially aligned;   said side wall openings and said flange openings substantially axially aligned;   a hinge pin rotatably positioned through said side wall openings and said flange openings;   said elongated extension arm having a first end and a distal second end;   said first end connected to said flanges;   said elongated extension arm extending from said flanges at a position offset from said flange opening axis; and   said attachment means connected to said extension arm proximal said second end.   
     
     
       8. A level sensor offset mounting mechanism as claimed in claim 7 wherein said locking means comprises: at least one offset position detent receiver in each of said side wall's exterior surface;   at least one insertion position detent receiver in each of said side wall's exterior surface;   at least one detent in each of said flange's interior surface;   said at least one detent constructed and positioned to engage said at least one offset position detent receiver when said elongated extension arm is in said offset position; and   said at least one detent further constructed and positioned to engage said at least one insertion position detent receiver when said elongated extension arm is in said insertion position.   
     
     
       9. A level sensor offset mounting mechanism as claimed in claim 8 wherein: the number of offset position detent receivers is two; and   said offset position detent receivers are vertically-aligned with and equidistant from said side wall openings.   
     
     
       10. A level sensor offset mounting mechanism as claimed in claim 8 wherein: the number of insertion position detent receivers is two; and   said insertion position detent receivers are horizontally-aligned with and equidistant from said side wall openings.